Should early 20th century researcher Paul Kammerer be credited as the founder of epigenetics? It would certainly be a dramatic change from current perceptions of his work.

Kammerer, a leading proponent of the Lamarckian theory of evolution, achieved global prominence in the 1920's by arguing that acquired traits could be passed down through generations and, in his most controversial experiment, forced land dweller midwife toads to live in water. Their offspring preferred to live and mate in water and by the third generation he noted that they began to develop black nuptial pads on their forelimbs, a feature common to water dwelling species.

In 1926 Kammerer fell into disgrace when it was found that his only remaining fixed specimen had been injected with India ink to produce the appearance of the black nuptial pads. Kammerer's role in the alleged fraud was never proven and six weeks after its discovery he committed suicide. Eventually, a naturally occurring specimen with nuptial pads was found, demonstrating that midwife toads do have the potential to develop them.

Writing in The Journal of Experimental Zoology, Dr. Alexander Vargas from the University of Chile says that Kammerer was actually decades ahead of his contemporaries and should be considered the founder of epigenetics.

"Today Kammerer's scientific legacy is non-existent and he is often cited as an example of scientific fraud," said Vargas. "However, the specific similarities of Kammerer's experiments to epigenetic mechanisms are very unlikely to have been the result of his imagination. These new biological arguments provide a modern context suggesting that Kammerer could be the actual discoverer of epigenetic inheritance."

Vargas says he has studied Kammerer's evidence, as summarized in his 1920's research notes, and found that Kammerer reported hybrid crosses of treated and untreated toads in which 'parent-of-origin effects' can be observed, a recurrent phenomenon in epigenetics. Kammerer also reported that his toads developed larger bodies than untreated land toads and that their eggs were smaller and contained less egg-yolk than normal. These are traits that are known to be influenced by epigenetic mechanisms.

Building on these observations Vargas proposes a preliminary model based on current knowledge of epigenetics to explain the midwife toad experiments, which illustrates how in a modern context an explanation can be offered for results which appeared utterly mysterious to Kammerer and his contemporaries.

Kammerer's consistency with current epigenetic mechanisms provides new and compelling biological arguments in favor of the authenticity of the midwife toad experiments, says Vargas.

"New experimentation on this species with the advantage of modern molecular-genetic tools could mean an end to the controversy," added Vargas. "If Kammerer's data is correct, the midwife toad holds the potential of becoming an excellent model system for studying epigenetics and especially its evolutionary implications."

Comments

Comments

Darwin was on target stating, “Lamarck, who believed in an innate and inevitable tendency towards perfection in all organic beings, seems to have felt this difficulty so strongly that he was led to suppose that new and simple forms are continually being produced by spontaneous generation. Science has not as yet proved the truth of this belief.”

Science still has not discovered "spontaneous generation." Remember Pasteur. Aspiring to be Larmackian Experimentalist seems to be a dubious honor.

I agree that Lamarck was not right 200 years ago and Kammerer was not right 100 years ago. The jury is out on Kammerer but I think it's unfortunate that Lamarck gets a bad rap. Stephen Jay Gould stopped getting kicked around a few years after he died so it's time to put Lamarck in his historical context and let it go otherwise.

There seems to be a trend today that labels anything as LaMarckian" if the idea involves something inherited environmentally. This can be confused with LaMarck's other beliefs that an internal will was involved and eventually humans would become angels, etc. This story invokes LaMarck not for his ideologies behind his scala natura, but for the general principle that traits can be changed by the environment and passed onto progeny. What LaMarck did was take good observations and attach theology to it, which fortunately, is not science by today's standards.

When I first started studying evolution seriously, I couldn't help but feel like there was a missing mechanism, and it seemed all too convenient that a purely genetic mutation in just one organism at a time could be responsible for the level and rates of diversity we see around us and in the fossil record. So, to me, the new work coming out in epigenetics is completely revolutionary and entirely welcome, because it's the piece I felt was missing all along. It's another trick in the bag, which reinforces the complexity of it all. Like any great scientific story, it raises more questions than it supplies answers - this is why I love science, and especially geology and evolution! Now if this research can move forward and come into greater understanding broadly across the body of science and scientists, without the confusion of the LaMarck connotations, we'll be in much better shape.

This gets me confused. Is this caused by (science) journalisms love of controversy?

First, I don't understand how an epimutation (say DNA methylation) in somatic tissue can be transfered to the germline. Second, how does the old experiments of August Weismann hold water against this? He is said to have disproved soft inheritance by cutting the tails off mice. Further, Jews and other religious groups have been circumcising men for hundreds of generations with no noticeable withering of the foreskin among their descendants.

I can see hos epigenetic marks can be inherited in a selfish-gene way like in genetic drive, where only the allele of one parent is expressed. I am also willing to account for epigenetic mutations during foster development, and the possibility that these mutations are inherited for a few generations.

However, there is still a long way to give soft-inheritance all the credit its getting in popularized science right now. There might be some intriguing patterns as a result of experiments, like in chicken and mice, but there is still now causal relationship described that can explain these patterns. Further, the Vargas paper is based on a theoretical model and not on experimental data. Before its time to revive Lamarck, proper experiments must be carried out. It is not only up to the advocators of epigenetical inheritance to re-make Kammerers experiment, but also to describe tha causal relationship between epigenetic mutations and how these enter the germline. Furthermore, DNA mutations in other genes, like gene regulatory sequences, must be ruled out. Once these experiments have been made, with results in favour of Kammerers suggestions, its time to go public.

Right now, theoretical suggestions are shouted out loud all over the world, without a proper scientific back-up.

Editors and journalists sometimes take advantage of the fact that the sizzle often sells more than the steak and, at least in America, people love the notion of the oppressed underdog even if it's misplaced. If you see the words 'dogma' and 'establishment' it is someone with a fringe theory who thinks they are being held down by entrenched notions of science.

Right now, theoretical suggestions are shouted out loud all over the world, without a proper scientific back-up.

A very small number of scientists do this - but I agree with you, and in those instances they even misuse the word 'theory' because it is more conjecture. However, fellow scientists are downright vicious in debunking the more ridiculous claims, which then leads to hurt scientists claiming that 'dogma' word.

I'll leave the rest of your comment to Mike because he can provide a better answer. He also wrote the oppressed article above and has done plenty of debunking of ridiculous claims by other scientists ... actually, his expertise in all of the above pretty much made my comment irrelevant.

"Right now, theoretical suggestions are shouted out loud all over the world, without a proper scientific back-up"

The same can be applied to Kammerer's critics, who simply assumed the data were simply entirely false, without any of them ever making any serious attempt to repeat his experiments.

You cannot comment on this case unless you know a teeeny-weeny bit about modern experiments in epiegentics, which show environmental effects on the germ-line and therefore, on inheritance. Do you know what a "parent-of-origin effect" is? Because the fact kammerer reported these in his experiments is, indeed, quite suggestive of authenticity.

Perhaps I put it all wrong. I did not mean to criticise Kammerer, I don't know much about him, his experiments or is opponents except for the inc thing. Now, what I wanted to stress is more about modern epigenetics, and even more so its modern interpretors in science media. I can understand genetic imprinting and environmentally induced epimutations during foster-development. That makes sense, even though my knowledge about molecular genetics might be "teeny-weeny" compared to Anonymous. What I cannot understand is the notion, proposed in some media, that our everyday life could affect the gene expression pattern in our offspring. For that to be true, there must be some strange signal going from the soma to the germ-line. Further, I get the impression from popular media that the epigenetic status of a gene is independent from genetic factors. I thought it was rather the opposite, and that problems like cancer starts when something goes wrong, and deviating form the genetically determined pattern.

I'm only trying to understand here. I'm trying to understand what is shouted out loud and mix it with my prior knowledge in biology. This is not a battle between August Weismann and Paul Kammerer. It's about understanding the world.

There is an entire literature on epigenetic inheritance. Read it. There is a fairly recent review article by Jablonka The "notion" (as you call it) of epigenetic inheritance is NOT something that has been "proposed" by the "media." It is a very real phenomena in many taxa and an active area of scientific research.

Even though I am not in the field of epigenetics, I consider my self rather well acquainted with the phenomenon as it is reported in the literature. My own interpretation of the literature is, as I stated above, that there are true examples of epigenetic inheritance. However, the molecular mechanisms for such inheritance, as far as I understand it, require the epimutations to originate in the germline (say in humans, I'm not thinking about plants which is a different matter).

So my question is, how can epigenetic mutations in the soma be transferred to the germline, and therefore also be inherited to the next generation?

I am well aware of the fact that just because the mechanism is not known it doesn't mean that it cannot exist. However, It is still interesting to ask the question. Further, as I understand it, there are mechanisms, guided by RNAi in Arabidopsis, that can remove epimutations after some generations. This suggests (understatement) that there is a genetic base for control of epigenetic status. All taken together, my personal impression is that the popular science version of epigenetic inheritance is over simplified. Popular science must be simplified, I understand that, but for me the interesting questions can be read between the lines.

Please note that these are my own personal reflections, caused by a sincere will to understand the evolutionary process and its mechanisms. I am not on a personal vendetta against epigenetics, to me the field is very promising and truly interesting. I really appreciate all comments, thank you all.